These stories got a different spin in the media, depending on which outlet covers them. Some chose a headline like ”Fukushima Radiation below permitted levels”, as if nothing extraordinary happened when the Fukushima reactors melted down. Others opted for a more balanced headline like “WHO releases mixed Fukushima radiation report”, but still struggled with the interpretation of the numbers. The WHO report confirmed that a large part of the population in Fukushima prefecture has been exposed to radiation levels between 1 - 50 millisievert in the past year (1 mSv is the internationally accepted maximum allowable dose for members of the public). This seems harmless, as many have started to believe that only above 100 mSv does the risk of cancer increase (see for example “The Children of Fukushima wait for UN study”).

In fact, there is no safe dose of radiation: any increase in radiation exposure increases cancer risks, the International Commission on Radiological Protection says. Hence when a large population (as in Fukushima) is exposed to radiation between 1-50 mSv, an increase in cancer and other health risks is expected. These health risks are hard to identify in scientific studies, as they are often hard to distinguish against the background of health risks due to other causes.

No nuclear spin can hide that a large population in Japan is still being exposed to higher levels of radiation than is normal. The WHO report is merely a first indication of how the public has been exposed, but in no way an evaluation of the health impacts of the radiation from the Fukushima disaster. The full impact of the disaster will only become known in time. Until then, much more emphasis needs to be placed on protecting the people in the contaminated areas. Not only the people in the highest exposure areas need to be protected, but measures need to be put in place to keep the radiation exposure of all people as low as possible.

"In fact, there is no safe dose of radiation: any increase in radiation exposure increases cancer risks, the International Commission on Radiolog...

"In fact, there is no safe dose of radiation: any increase in radiation exposure increases cancer risks, the International Commission on Radiological Protection says. Hence when a large population (as in Fukushima) is exposed to radiation between 1-50 mSv, an increase in cancer and other health risks is expected. These health risks are hard to identify in scientific studies, as they are often hard to distinguish against the background of health risks due to other causes."

Yes, the reason why they are hard to detect is because they are so incredibly small. After Chernobyl, around 100 children died of thyroid cancer and 4000 had to have operations, but according to WHO, UNSCEAR and others, there was no detectable increase in any kind of cancer or other effects. The doses from Fukushima are lower than Chernobyl, and the death toll from both combined will be less than 10,000. Compare these consequences from two nuclear accidents 25 years apart with the ongoing effects of burning coal, driving cars etc - 10,000s of deaths a year. Nuclear hardly carries the 'high risks' you claim now does it?

The Linear-No-Threshold radiation dose standard was only implemented as a convenience for the nuclear industry. It was easier to promise to keep doses...

The Linear-No-Threshold radiation dose standard was only implemented as a convenience for the nuclear industry. It was easier to promise to keep doses very low rather than use scientific evidence to adopt a real, but more complicated, threshold based model. LNT is only a hypothesis and now that radiation has been released, its important to abolish this outdated and inaccurate, overly conservative policy, so that the people of Fukushima may return to their homes and live in peace.

The residents of Ramsar Iran are exposed to 132mSV every year and there have been no additional cancers. Dr. Mortazavi has said "The risk from exposure to low-dose radiation has been highly politicized for a variety of reasons. This has led to a frequently exaggerated perception of the potential health effects, and to lasting public controversies." (http://www.angelfire.com/mo/radioadaptive/ramsar.html)

Regarding your claim that “In fact, there is no safe dose of radiation: any increase in radiation exposure increases cancer risks, the International C...

Regarding your claim that “In fact, there is no safe dose of radiation: any increase in radiation exposure increases cancer risks, the International Commission on Radiological Protection says. Hence when a large population (as in Fukushima) is exposed to radiation between 1-50 mSv, an increase in cancer and other health risks is expected,” please note that according to ICRP Publication 103, “The 2007 Recommendations of the International Commission on Radiological Protection,” item ‘k’, page 13:
“Collective effective dose is not intended as a tool for epidemiological risk assessment, and it is inappropriate to use it in risk projections. The aggregation of very low individual doses over extended time periods is inappropriate, and in particular, the calculation of the number of cancer deaths based on collective effective doses from trivial individual doses should be avoided.”

If one chooses to ignore ICRP’s caveat against the calculation of cancer deaths based on collective effective doses from trivial individual doses, it is possible to arrive at ridiculous results.

To demonstrate how such calculations of low doses of radiation lead to absurd results, we need only to look at cosmic rays on earth, and the way the rate varies with altitude (because of the reduction of shielding provided by the Earth's atmosphere, which decreases with altitude).

As shown in the graph below, there is a variable rate of cosmic radiation in major cities worldwide, according to their altitude above sea level. The rate increases by about 0.1 micro-Sieverts per year per meter of altitude (0.1 uSv/year/m).
From this well known number, we can calculate the effect of wearing high-heeled shoes.
With a 7 centimeter high heel, the increase in altitude increases the radiation dose by 0,1 uSv/year/m x 0,07m = 0,007 uSv/year.

Now, if we assume that this applies to most women on earth, for multiple generations for thousands of years, we can project the total radiation impact for high heel shoes, using the LNT relationship of 0.05 fatal cancers per Sievert per person:
0,07m x 0,1E-06 Sv/year/m x (8h with shoes/24h) x 2E+09 persons x 100,000 years x 0.05 deaths/Sv/person = 23,000 deaths from cancer.

Of course no one can seriously believe this figure of 23,000 deaths from cancer due to increased radiation dose for wearers of high-heeled shoes!
Moreover, it is well known from epidemiological studies over past decades, that cancer rates in urban populations at high altitude are no higher than those at low altitude - quite the opposite!

The global population average exposure to natural radiation (cosmic AND terrestrial, including Radon) is 2.4mSv per year, with a typical range of 1mSv to 13mSv per year.

On a regional level, there are populations in certain parts of the world where average exposure to natural radiation is much higher, due to natural radioactive minerals in rocks or dissolved in ground water.
For example, people in some areas of Ramsar, a city in northern Iran, receive an annual radiation dose from background radiation that is up to 260mSv per year (typical range in the high background areas is 8 to 80mSv/y).
Inhabitants of Ramsar have lived for many generations in these high background areas: Greenpeace never told them to evacuate, presumably because the radiation didn’t come from Fukushima.
Cytogenetic studies show no significant differences between people in the high background compared to people in normal background areas.

Similar high-exposure populations occur in Kerala, India, in Guarapari, Brazil, and in Yangjiang, China, again showing no significant differences between people in the high background compared to people in normal background areas.

The Fukushima population exposures are indeed trivial: As ICRP cautions, calculation of the number of cancer deaths based on trivial radiation doses should be avoided.

The Health Physics Society published a position statement titled Radiation Risks in Perspective that includes valuable information that helps people understand what scientists really mean when they say that they have assumed that there is risk associated with any dose of radiation.

http://hps.org/documents/risk_ps010-2.pdf

Here is an important quote from the summary:

"There is substantial and convincing scientific evidence for health risks following high-dose exposures. However, below 5–10 rem (which includes occupational and environmental
exposures), risks of health effects are either too small to be observed or are nonexistent."

Note: 5-10 rem = 50-100 mSv.

Like most humans, I recognize that life is uncertain and that nearly every decision I make includes some amount of risk. I am terribly concerned about the future prospects of human society if we cannot move to an ultra low carbon energy supply system.

Nuclear energy is clean enough to run inside sealed submarines and is vastly superior to all other alternatives.

Concerning the risk of nuclear power, I notice within my circle of colleguea and acquantainces w...

Thanks for the comments on this article.

Concerning the risk of nuclear power, I notice within my circle of colleguea and acquantainces which include anti-nuclear supporters who are members of Green Peace, that the realisation is becoming more widespread that resistance to nuclear energy *in principle* is no longer a sensible position to take for a serious environmentalist.

It has now become clear by now that non-nuclear ultra-low carbon energy options have failed - and will almost certainly continue to fail - to adequately substitute for high-carbon energy sources.

Environmentalists world wide - including those at Green Peace - really need to take a step and re-evaluate the nuclear option based on current state of affairs and prospects. 35 years ago the case could be made that a transition to non-carbon, non-nuclear sources of energy might be made in time, but today (unfortunately) given the current world economic headwinds and close threat of various resource shortages, there has to be a sensible reevaluation of nuclear power.

I think Greenpeace cannot afford to maintain its antinuclear agenda. I think it should be possible for Greenpeace to revisit it's principles on this issue and embrace nuclear energy. I dare to think that a sizeable part of Greenpeace core supporters (of which I have also been one) are ready to do this as soon as possible.

Funny. If someone told me to choose an energy source that's been around almost sixty years worldwide and even including its worst rare nightmare d...

Funny. If someone told me to choose an energy source that's been around almost sixty years worldwide and even including its worst rare nightmare day hasn't killed more total people than one small jet crash -- for energy whose literal fossil fuel record has for hundreds of years killed and blighted millions of adults and kids alike with respiratory diseases and pollution to this very day -- not to talk about oil and gas accidents that literally take whole towns with them, I'd have to be one fanatic hypocrite to chose oil and coal and gas over nuclear. Yes, Oil and Gas have lots to fear from nuclear -- with lots of commercials...

I've been around from Earth Day One and nothing has wavered my support of nuclear power. Today I see a lot more reality-warping fear-mongering for sure and less followers willing to check out the facts. If anything I firmly believe now that most anti-nuclear supporters are in it for philosophical grievances or than safety or health; call it avenging Hiroshima guilt trips for the somehow uniquely evil thing the atom did there, or many it's all those nuclear-smitten B-movies from the fifties. Whatever, you just can't hit nuclear on the life, health and safety issue. The record's there for all to see -- and warp. Smearing it with "what if" nightmare scenarios won't cut it after sixty years of chances for Doomsday to happen. Moreever, it's telling that no top anti-nuclear activists dare take on true nuclear professionals the likes of Rod Adams or Will Davis in a toe-to-to debate rather than with select token media darling "experts". To me that says it all about the credibility of much amoured anti-nuke "champions" who are AWOL about generations of kids with respiratory diseases from fossil fuels. If I'm wrong, then where's the challengers to a debate??

To say there's no safe level of radiation -- Please! Here in NYC you can have fun listening to Geiger counters click away in places like Grand Central Station from the granite and marble emissions (the MTA police there have to take this into account for dirty bomb sweeps), the Empire State Building, Grants Tomb, and literally thousands of work and living structures, and I don't exactly see people swooning from radiation poisoning here next to mutant kids. To listen to GP & Co, you'd swear this island ought resemble the Forbidden Zone from the Planet of the Apes by now. And let's not even get into the media-shy secret of thriving cities around the would with far far higher background rad readings than bad ole Fukushima.

FDR said we have nothing to fear but fear itself. Followers of Greenpeace and other "eco-minded" organizations ought take this in stride and start questioning their leadership and idols and THEIR "facts" with the same passion you assail the opposition.

I see no consistency in comparing the possible deaths of Fukushima with levels of radiation. As has been said here, there is no safe number of how our...

I see no consistency in comparing the possible deaths of Fukushima with levels of radiation. As has been said here, there is no safe number of how our body can absorb radiation, but these studies are not considering the quality of life of the people involved. Perhaps 10,000 people will die in the coming years victims of Chernobyl and Fukushima, but how many die each year from coal and gas? How many people abandoned their homes due to dam constructions? Even with few accidents, nuclear power can be better and less dangers if compared with another sources of power. The number of injury and deads it's too low. Sorry my poor english, I'm brazilian, hope you all can understand me!

A recent study from MIT scientists suggests that the guidelines governments use to determine when to evacuate people following a nuclear accident may...

A recent study from MIT scientists suggests that the guidelines governments use to determine when to evacuate people following a nuclear accident may be too conservative.
A new look at prolonged radiation exposure MIT study suggests that at low dose-rate, radiation poses little risk to DNA.
http://web.mit.edu/newsoffice/2012/prolonged-radiation-exposure-0515.html

"High nuclear radiation doses are delivered during a course of radiotherapy (RT) by aiming beams of radiation to kill the tumour cells. Millions ...

"High nuclear radiation doses are delivered during a course of radiotherapy (RT) by aiming beams of radiation to kill the tumour cells. Millions of patients each year around the world receive such treatment and most return home thankful for more years of fruitful life. Such a course may last 4-6 weeks with a daily dose of 2,000mSv given each time to the tumour. Unfortunately it is not possible to restrict the radiation to the tumour alone and neighbouring tissue and organs may get as much as 1,000mSv each day - and these can indeed survive the RT course. Over a month the tumour gets more than 40,000mSv and the peripheral healthy tissue as much as 20,000mSv - that is five times the fatal
dose experienced by some Chernobyl workers! Here is a very simple sketch of how it works.
Each day the cells attempt to repair the damage caused by the radiation. For the tumour cells the repair mechanisms are marginally overwhelmed, and for the peripheral tissue with its lower dose the mechanisms are just able to complete repairs before the next day. This separation of the dose into daily treatments is named "fractionation". After 4 to 6 weeks the tumour is hopefully dead and the peripheral tissue survives". (Prof. Wade Allison Oxford University from the "Public Trust in Nuclear Energy")
http://www.radiationandreason.com/

As stated above, Collective dose should not and cannot be used to look at stochastic risk in a large population exposed to very low doses of ionising ...

As stated above, Collective dose should not and cannot be used to look at stochastic risk in a large population exposed to very low doses of ionising radiation (external or internal - where effective dose is used as the measure).